Hello, Thank you for using HCM. I understand your concern with the nasal congestion symptoms and use of diominic dca tablets while you have high blood pressure. Nasal congestion is very common in common cold and is very self limiting but sometimes the distress it gives with inability to breath especially at sleep is really uncomfortable. The tablets you mention have phenilephrine and might cause racing heart and sometimes high blood pressure especially when taken orally. There are several things to try to help with your symptoms: 1. Nasal lavage (rinse) with saline solution- it helps soften and clear secretions and may make you feel better. In you tube there are videos that explain how to have an effective nasal rinse with saline solution. 2. Local treatment with drops in both nostrils- nasal decongestant drops are helpful but should not be used for more than 5 days due to rebound effect (symptoms get worse when you stop them if you use them for more than 5 days). These still have a very small and uncosiderable chance of causing high BP but it is very unlikely comparted to the oral decongestants. 3. Some studies have shown recently that nasal steroids can be helpful also in symptom relive in nasal congestion due to viruses. These steroid drops or spray have generally been used for allergic rhinitis but studies recommend their use also in nasal congestion of viral origin if symptoms are so severe. 4. make sure you keep yourself hydrated and drink plenty and avoid dry air. Nasal mucosa is in direct contact with the air and is very sensitive to the humidity and temperature of the air. 5. something practical is also to raise up a little the head of the bed so you are not totally head down and this might give mild improvement of your symptoms. Hope this is helpful and answers to your question